const int analogOutPin=6;
int ledLight=0;
void setup() {
 

}

void loop() {
  while(ledLight/256==0)
  {
    ledLight++;
    ledLight%=256;
    analogWrite(analogOutPin,ledLight);
  }
  while(ledLight/256!=0)
  {
    ledLight--;
    ledLight%=256;
    analogWrite(analogOutPin,ledLight);
  }
  
}
